Naval Architecture Dictionary Entry
Deadweight Tonnage (DWT)
"A measure of how much weight a ship can carry. It is the sum of the weights of cargo, fuel, fresh water, ballast water, provisions, passengers, and crew."
Definition
Deadweight Tonnage (DWT) represents the total lifting capacity of a ship in tons. It is not the weight of the empty ship itself (which is Lightweight Tonnage), nor is it the volumetric capacity (which is Gross Tonnage).
Formula
DWT = Displacement (at max draft) - Lightweight
- Displacement: Total weight of water displaced by the ship.
- Lightweight: Weight of the ship structure + machinery (empty).
Usage
DWT is the primary metric used in chartering to describe the size of cargo ships (e.g., "A 50,000 DWT Bulker").
Related Terms
DraftDisplacementTonnage Calculator